Problem: What is the numerator of the fraction $\dfrac{4}{9}$ ?
Explanation: Fractions help represent parts of a whole. The fraction $\dfrac{4}{9}$ could represent 4 out of 9 slices of pie. In other words, the pie has been cut into 9 slices, and we are only considering 4 of those slices. $=\dfrac{{4}}{9}=\dfrac{{\text{numerator}}}{\text{denominator}}$ The numerator is the number of slices we consider, and it is written above the fraction line. The denominator is the total number of slices, and it is written below the line. Thus, the numerator is $4$.